U.S. patent number 5,989,210 [Application Number 09/019,728] was granted by the patent office on 1999-11-23 for rheolytic thrombectomy catheter and method of using same.
This patent grant is currently assigned to Possis Medical, Inc.. Invention is credited to William J. Drasler, Robert G. Dutcher, Hieu V. Le, John Edward Morris, Cindy M. Setum.
United States Patent |
5,989,210 |
Morris , et al. |
November 23, 1999 |
Rheolytic thrombectomy catheter and method of using same
Abstract
A surgical device and method for removal of tissue, such as
thrombus, from a vessel in the body. The device has a first tube
with a distal open end and an inward directed stop and a second
tube with an outward directed stop for engaging the inward directed
stop and thereby regulating the relationship between a retrograde
jet and the distal open end. Thrombus is dislodged, entrained, and
broken into pieces which are evacuated through the first tube.
Inventors: |
Morris; John Edward
(Minneapolis, MN), Setum; Cindy M. (Plymouth, MN),
Drasler; William J. (Minnetonka, MN), Le; Hieu V.
(Minneapolis, MN), Dutcher; Robert G. (Maple Grove, MN) |
Assignee: |
Possis Medical, Inc. (Coon
Rapids, MN)
|
Family
ID: |
21794707 |
Appl.
No.: |
09/019,728 |
Filed: |
February 6, 1998 |
Current U.S.
Class: |
604/22; 604/508;
604/523 |
Current CPC
Class: |
A61B
17/32037 (20130101); A61B 17/32075 (20130101); A61B
2090/034 (20160201) |
Current International
Class: |
A61B
17/22 (20060101); A61B 19/00 (20060101); A61B
017/20 () |
Field of
Search: |
;604/22,49,52-54,164-165,170,264,280,283,266,267 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Coggins; Wynn Wood
Assistant Examiner: Thanh; LoAn H.
Attorney, Agent or Firm: Jaeger; Hugh D.
Claims
It is claimed:
1. A catheter for removing material from a body cavity
comprising:
a. an outer assembly including
(1) a first tube having a lumen with an open distal end and an
internally located stationary stop partially obstructing said lumen
at said open distal end and,
b. an inner assembly including
(1) a second tube insertable into said first tube, said second tube
having a high pressure lumen having a distal end, said distal end
having an orifice;
(2) a transitional stop fixed to said second tube adjacent to said
distal end; and,
(3) means positioned at said distal end of said second tube and
coacting with said distal end of said second tube for directing
fluid exiting said orifice toward said open distal end of said
first tube, said second tube being movable axially within said
first tube such that said transitional stop engages said stationary
stop to hold said means in a desired relationship with respect to
said open distal end of said first tube.
2. A catheter for removing material from a body vessel or other
body cavity comprising:
a. an outer assembly including
(1) an evacuation tube having a proximal end and an open distal end
containing a stationary stop and having an evacuation lumen;
and,
b. an inner assembly including
(1) a high pressure tube having a high pressure lumen, said high
pressure tube having a proximal end and a distal end, said distal
end having one or more orifices through which fluid can exit from
said high pressure lumen to be directed toward said open distal end
of said evacuation tube;
(2) a transitional stop fixed to said high pressure tube at a
position closer to said distal end than to said proximal end;
and,
(3) means positioned at said distal end of said high pressure tube
and coacting with said distal end of said high pressure tube to
direct fluid toward said open distal end of said evacuation
tube.
3. The catheter of claim 2, wherein said means has a distal end and
said distal end of said jet cap has a guidewire coil attached
thereto to assist in advancement of said outer assembly and said
inner assembly together or separately within the body vessel or
other body cavity.
4. The catheter of claim 2, wherein said means is configured to
create a jet of fluid and to direct it toward said open distal end
of said evacuation tube.
5. The catheter of claim 2, wherein said evacuation tube is
flexible and can pass over a guidewire through tortuous
pathways.
6. A method of removing material from a body vessel or other body
cavity comprising the steps of:
a. providing a guidewire and a first catheter having an open distal
end and an internally located stationary stop positioned adjacent
to the open distal end;
b. advancing the guidewire to a body cavity site containing
material to be removed;
c. advancing the first catheter over the guidewire to the body
cavity site containing material to be removed to position the
distal end at the body cavity site;
d. removing the guidewire from the first catheter;
e. providing a second catheter carrying a means for directing fluid
and a transitional stop spaced apart from the means for directing
fluid;
f. advancing the second catheter within the first catheter to
engage the transitional stop with the stationary stop; and,
g. providing a high pressure fluid supply to the second catheter so
as to cause fluid to emanate therefrom and to impinge upon and
dislodge the material to be removed and force it into the open
distal end of the first catheter.
7. The method of claim 6, wherein the means for directing fluid
carries a distally projecting coil to facilitate further distal
advancement of the first catheter and the second catheter together
or separately within the body vessel or other body cavity to a
further body cavity site containing material to be removed so as to
remove additional distally situated material.
8. A catheter combination comprising:
a. a first tube having an open distal end and a lumen extending to
the open distal end;
b. a second tube, separable from the first tube, and insertable
within the lumen of the first tube, the second tube having a distal
end and a lumen extending to the distal end;
c. means connected to the second tube at the distal end of the
second tube and coacting with the distal end of the second tube for
directing fluid exiting the lumen of the second tube, toward the
open distal end of the first tube, said means being capable of
passage through the lumen of the first tube and being characterized
by the ability to provide a localized region of low pressure
associated with a liquid flow directed generally proximally and
into the lumen of the first tube through the open distal end of the
first tube when located and oriented appropriately relative to the
open distal end of the first tube; and,
d. means for indexing an appropriate positional relationship of
said means and the distal end of the second tube relative to the
open distal end of the first tube, the means for indexing
comprising a transitional stop fixed to the second tube adjacent to
the distal end of the second tube.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a rheolytic thrombectomy catheter
and method of using same to remove thrombus from a body vessel or
other body cavity.
2. Description of the Prior Art
Procedures and apparatus have been developed for ease in removing
tissue and various deposits. Several such devices employ a jet of
saline as the working tool to help break up the tissue deposit and
further provide a suction means to remove the deposit. U.S. Pat.
No. 5,135,482 to Neracher describes a hydrodynamic device for
removal of organic deposit from a human vessel. A supply of saline
is delivered by a high pressure duct to the distal end of a
catheter. The saline exits the duct as a jet that is directed
generally forward and directly toward the tissue to be broken up.
The duct is contained within and can move axially with respect to a
hose that is positioned around the duct. A vacuum suction is
applied to the hose to remove the debris that is created from the
broken-up tissue. This device is not intended to pass through
tortuous pathways found in the fragile vessels of the brain, and
any attempt to employ the device for such purpose would be far too
traumatic to the patient.
Another drainage catheter, described by Griep in U.S. Pat. No.
5,320,599, has a discharge channel and a pressure channel. The
channels are formed into a single catheter tube such that the two
tubes are fixed with respect to each other. This catheter could not
provide the flexibility needed to negotiate the tortuous vascular
pathways found in the vessels of the brain.
SUMMARY OF THE INVENTION
The general purpose of the present invention is to provide a
rheolytic thrombectomy catheter and method of using same to remove
thrombus from a body vessel or other body cavity.
The present invention, a rheolytic thrombectomy catheter, is a
surgical device for removal of material such as thrombus from a
vessel or other body cavity. As shown in one or more embodiments, a
rheolytic thrombectomy catheter for removing tissue from a vessel
or other body cavity includes an outer assembly comprising a first
tube or guide catheter having a lumen with an open distal end and
an internally and distally located stationary stop partially
obstructing the lumen at the open distal end, the lumen being of a
diameter sufficient to allow passage of a guidewire; and an inner
assembly comprising a high pressure second tube or hypo-tube having
a high pressure lumen and a distal end having one or more orifices,
a distally located transitional stop fixed to the high pressure
hypo-tube adjacent to the distal end, and means characterized as a
jet cap positioned at and coacting with the hypo-tube distal end
for directing one or more jets of saline toward the distal end of
the guide catheter, the inner assembly being movable axially within
the outer assembly such distally located transitional stop engages
the stationary stop to hold the jet cap in a desired relationship
with respect to the distal end of the guide catheter.
In another embodiment, a rheolytic thrombectomy catheter for
removing thrombus or other body tissue from an obstructed body
vessel or other body cavity includes an outer assembly including an
evacuation tube having a proximal end and an open distal end
containing a distally located stationary stop and having an
evacuation lumen that is of a diameter sufficient to allow passage
of a standard coronary or interventional neuroradiological
guidewire; and an inner assembly including a high pressure
hypo-tube having a high pressure lumen, the high pressure hypo-tube
having a proximal end and a distal end, the distal end having one
or more orifices through which saline can exit from the high
pressure lumen to be directed toward the open distal end of the
evacuation tube, a transitional stop fixed to the high pressure
hypo-tube at a position closer to the distal end than to the
proximal end, and and means characterized as a jet cap positioned
at the distal end of the high pressure hypo-tube, the jet cap
coacting with the high pressure hypo-tube to direct one or more
jets of saline toward the open distal end of the evacuation
tube.
Preferably, the rheolytic thrombectomy catheter has a guidewire
coil attached at the distal end of the jet cap to allow advancement
of the inner assembly and the outer assembly together within the
vasculature. Preferably, the rheolytic thrombectomy catheter has a
jet cap which directs a jet of saline toward the distal end of the
guide catheter, which functions as an evacuation tube. Preferably,
the rheolytic thrombectomy catheter includes a high pressure
hypo-tube with at least one orifice and a jet cap configured and
arranged for directing one or more jets of saline to impinge upon
or near the distal end of the guide catheter. The rheolytic
thrombectomy catheter preferably is flexible and can pass over a
standard guidewire through tortuous vascular pathways.
The present invention also provides a method of removing thrombus
from an obstructed body vessel. The method includes the steps
of:
a. providing a guidewire and an outer assembly including a guide
catheter having a distal end and an internally located stationary
stop positioned adjacent to the distal end;
b. advancing the guidewire to a vascular site containing
thrombus;
c. advancing the guide catheter over the guidewire to the vascular
site containing thrombus to position the distal end at the vascular
site;
d. removing the guidewire from the guide catheter;
e. providing an inner assembly including a hypo-tube carrying a jet
cap and a transitional stop spaced apart from the jet cap;
f. advancing the inner assembly within the guide catheter of the
outer assembly to engage the transitional stop with the stationary
stop; and,
g. providing a high pressure saline supply to the hypo-tube so as
to cause a jet of saline to emanate from the jet cap and to impinge
on thrombus and on or near the distal end of the guide catheter,
thereby dislodging thrombus and entraining thrombus into the saline
jet and thence into the guide catheter.
In the method, preferably, the jet cap carries a distally
projecting guidewire coil to facilitate further distal advancement
of the inner assembly and the outer assembly together within the
vasculature to a further vascular site containing thrombus so as to
remove additional distally situated thrombus.
The present invention is also a catheter combination including a
first tube or guide catheter, being a part of an outer assembly,
the first tube having a proximal end, an open distal end, and a
lumen extending between the proximal end and the open distal end; a
second tube or hypo-tube, being a part of an inner assembly, the
second tube being separable from the first tube and being
insertable within the lumen of the first tube, the second tube
having a proximal end, a distal end, and a lumen extending between
the proximal end and the distal end; a jet cap, being also a part
of the inner assembly, the jet cap being connected to the second
tube at the distal end of the second tube for directing fluid
exiting the lumen of the second tube, the jet cap being capable of
passage through the lumen of the first tube and being characterized
by the ability to provide a localized region of low pressure
associated with a liquid flow directed generally proximally and
into the lumen of the first tube through the open distal end of the
first tube when the jet cap is located and oriented appropriately
relative to the open distal end of the first tube; and means for
indexing an appropriate positional relationship of the jet cap and
distal end of the second tube relative to the open distal end of
the first tube. The means for indexing preferably includes a
distally located stationary stop projecting inward from the first
tube and a distally located transitional stop projecting outward
from the second tube. When the second tube is advanced within the
first tube, the stops mutually engage to control the orientation
and spacing and relationship between the jet cap and the open
distal end of the first tube. More preferably, the stops are each
tapered to additionally laterally position the second tube within
the first tube. Most preferably, the centering causes the tubes to
become concentric. Preferably, one or both stops interact, when
engaged, to preserve a channel for fluid flow rather than fully
obstructing the cavity between the first tube and the second
tube.
One significant aspect and feature of the present invention is the
variously designed jet caps which are oriented to direct jets of
saline in a proximal direction.
Another significant aspect and feature of the present invention is
the stationary stop at the distal end of the guide catheter and the
distally located transitional stop on the hypo-tube which together
coact to position a jet cap at a defined distance beyond the distal
end of the guide catheter.
Still another significant aspect and feature of the present
invention is the distally located transitional stop which has an
evacuation lumen and a hypo-tube receiving hole which is offset
from the longitudinal axis of the distally located transitional
stop.
Yet another significant aspect and feature of the present invention
is the provision of complementary angled surfaces on the distally
located stationary and transitional stops which upon engagement
serve to center the inner assembly within the outer assembly.
A further significant aspect and feature of the present invention
is the distally located stationary stop which is formed unitarily
with the wall of the guide catheter at the distal end of the guide
catheter.
A still further significant aspect and feature of the present
invention is the guidewire coil provided at the distal end of the
jet cap to allow advancement of the inner assembly and the outer
assembly together within the vasculature.
Having thus described embodiments and significant aspects and
features of the present invention, it is the principal object of
the present invention to provide a rheolytic thrombectomy catheter
and method of using same to remove thrombus from a body vessel.
One object of the present invention is to provide a rheolytic
thrombectomy catheter of such size, flexibility and construction as
to enable it to pass readily through the tortuous pathways found in
the fragile vessels of the brain.
Another object of the present invention is to provide a rheolytic
thrombectomy catheter with means for producing one or more jets of
saline and projecting them in a proximal direction toward a site of
thrombus and toward an evacuation passage.
Yet another object of the present invention is to provide a
rheolytic thrombectomy catheter with means for producing one or
more jets of saline and with indexing means to position the jet
producing means at a prescribed location at the distal end of the
catheter.
Still another object of the present invention is to provide a
rheolytic thrombectomy catheter of the type having an inner
assembly that is insertable into an outer assembly with stop means
for limiting the extent to which the inner assembly can be inserted
into the outer assembly.
A further object of the present invention is to provide a rheolytic
thrombectomy catheter of the type having an inner assembly and an
outer assembly with means which centers the inner assembly within
the outer assembly and which orients the parts of the inner
assembly in a prescribed manner with respect to the parts of the
outer assembly.
A still further object of the present invention is to provide an
improved method of removing thrombus from an obstructed body
vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant
advantages of the present invention will be readily appreciated as
the same becomes better understood by reference to the following
detailed description when considered in connection with the
accompanying drawings, in which like reference numerals designate
like parts throughout the figures thereof and wherein:
FIG. 1 is a side view of the present invention, a rheolytic
thrombectomy catheter useful for the removal of thrombus;
FIG. 2 is a semi-exploded side view of the rheolytic thrombectomy
catheter depicting the two major assemblies thereof, viz., an outer
assembly and an inner assembly;
FIG. 3 is a semi-exploded cross sectional side view of a manifold
and adjacent components constituting parts of the outer
assembly;
FIG. 4 is a longitudinal sectional view of a filter housing/high
pressure connection assembly attached to the proximal end of a
hypo-tube, shown only partially;
FIG. 5 is a side view of a transitional stop, a jet cap, and a
guidewire coil aligned over and about the hypo-tube at the distal
end thereof;
FIG. 6 is an isometric view of the transitional stop;
FIG. 7 is a longitudinal sectional view taken along line 7--7 of
FIG. 5;
FIG. 8 is a view of the proximal end of the jet cap on the
hypo-tube looking in the direction of line 8--8 of FIG. 7, with the
hypo-tube shown in cross section;
FIG. 9 is a view similar to FIG. 8 illustrating a slightly modified
version of the jet cap;
FIG. 10 is a longitudinal sectional view of the guide catheter
distal end taken along line 10--10 of FIG. 2;
FIG. 11 is a longitudinal sectional view of the guide catheter
distal end with the transitory stop, the jet cap, and the guidewire
coil on the hypo-tube shown advancing therethrough;
FIG. 12 is a longitudinal sectional view of the guide catheter
distal end with the transitory stop, the jet cap, and the guidewire
coil on the hypo-tube shown in final advanced position;
FIG. 13 is a cross-sectional view taken along line 13--13 of FIG.
12;
FIG. 14 is presented to illustrate schematically the mode of
operation of the rheolytic thrombectomy catheter, and is a
longitudinal sectional view depicting the distal end of the
rheolytic thrombectomy catheter within a blood vessel at the site
of a thrombotic deposit and lesion;
FIG. 15 is a longitudinal sectional view similar to FIG. 7 but
illustrating an alternative jet cap embodiment;
FIG. 16 is a view of the proximal end of the alternative jet cap
embodiment shown in FIG. 15 looking in the direction of line 16--16
of FIG. 15, with the hypo-tube shown in cross section;
FIG. 17 is a longitudinal sectional view similar to FIG. 15 but
illustrating another alternative jet cap embodiment;
FIG. 18 is a view of the proximal end of the alternative jet cap
embodiment shown in FIG. 17 looking in the direction of line 18--18
of FIG. 17, with the hypo-tube shown in cross section;
FIG. 19 is a longitudinal sectional view similar to FIG. 12 but
illustrating an alternative transitional stop embodiment;
FIG. 20 is a view of the guide catheter distal end looking in the
direction of line 20--20 of FIG. 19, with the hypo-tube shown in
cross section;
FIG. 21 is a view similar to FIG. 12 but illustrating alternative
embodiments of the transitional stop and the stationary stop;
FIG. 22 is a view of the guide catheter distal end looking in the
direction of line 22--22 of FIG. 21, with the hypo-tube shown in
cross section; and,
FIG. 23 is a side view in partial cross section of a fifth
alternative embodiment of the guide catheter distal end, where the
hypo-tube is fixed along the longitudinal axis of the guide
catheter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a side view of a rheolytic thrombectomy catheter
10 useful for the removal of thrombus, and FIG. 2 illustrates a
semi-exploded side view of the rheolytic thrombectomy catheter 10.
The rheolytic thrombectomy catheter 10 includes two major
assemblies: namely, an outer assembly 12 and an inner assembly 14.
The inner assembly 14 aligns concentrically to and within the outer
assembly 12 and extends beyond the length of the outer assembly 12.
Externally visible components, or portions of components, of the
outer assembly 12 of the rheolytic thrombectomy catheter 10, as
illustrated in FIGS. 1 and 2, include a manifold 16, also known as
a Y-adapter, a hemostasis nut 18 secured in the proximal end 20 of
the manifold 16, a Luer connection 22 located at the proximal end
23 of an angled manifold branch 24 extending from the manifold 16,
a Luer fitting 26 secured to the distal end 28 of the manifold 16,
a strain relief 30 secured to the distal end 28 of the manifold 16
by the Luer fitting 26, and a first tube or guide catheter 32,
having a distal end 33, secured to the manifold 16 by the strain
relief 30 and Luer fitting 26. The externally visible components of
the inner assembly 14, illustrated in FIG. 2, include a high
pressure second tube or hypo-tube 34, a filter housing/high
pressure connection assembly 36 concentrically aligned to and
secured over and about the hypo-tube proximal end 38, a configured
transitional stop 40 concentrically aligned to and secured over and
about the hypo-tube 34 at a point near and adjacent to the
hypo-tube distal end 42, a jet cap 44 concentrically aligned to and
secured over and about the hypo-tube 34 at the hypo-tube distal end
42, and a guidewire coil 46 concentrically aligned to and secured
to one end of the jet cap 44. The high pressure hypo-tube 34 is
drawn and is tapered in incremental steps to provide degrees of
flexibility along its length. For purposes of example and
illustration, the hypo-tube 34 can include a hypo-tube portion 34a
at the hypo-tube proximal end 38 having an outer diameter of 0.018
inch or smaller, and can include a plurality of incrementally
stepped down hypo-tube portions 34b-34n each of lesser outer
diameter, where the last hypo-tube portion 34n is stepped down to
an outer diameter .008 inch at the hypo-tube distal end 42. The
hypo-tube 34 becomes increasingly more flexible from the hypo-tube
proximal end 38 towards the hypo-tube distal end 42 due to the
incremental diameter decrease along its length. Increasing
flexibility along the length of the hypo-tube 34 allows for easier
flexed penetration into tortuous vascular paths. Although the
hypo-tube 34 is stepped down in increments, the hypo-tube 34 can
also be fashioned of a constantly decreasing outer diameter to
provide increasing flexibility along its length and shall not be
construed to be limiting to the scope of the invention.
FIG. 3 illustrates a semi-exploded cross sectional side view of the
manifold 16 and adjacent components, where all numerals correspond
to those elements previously described. The manifold 16 includes a
tapered centrally located passage 48 aligned along the longitudinal
axis of the manifold 16 and a branch passage 50 extending along the
axis of the branch 24 which intersects and is connected to the
central passage 48. The manifold proximal end 20 houses a
multi-radius cavity 52 including a round outer cavity portion 54
and a connected round inner and smaller cavity portion 56 having a
threaded surface 58 on the proximal portion thereof. The hemostasis
nut 18 includes a body 62 having a grasping surface 64 extending
thereabout, a threaded surface 66 extending from the body 62, an
annular surface 63 at the end of the threaded surface 66, and a
passageway 68 aligned centrally to the longitudinal axis of the
hemostasis nut 18. The passageway 68 has a wide radius at the
proximal end which decreases toward the distal end. The initial
wide radius is helpful for insertion of the inner assembly 14 or
guidewires and the like. A seal 60 aligns to the distally located
annular surface 61 of the round inner cavity portion 56 and bears
against the annular surface 63 of the hemostasis nut 18 to seal the
central passage 48 of the manifold 16 to the passageway 68 in the
hemostasis nut 18. The multi-radius cavity 52 and its internal
geometry accommodate corresponding geometry of the hemostasis nut
18 and the seal 60. Luer connection 22 extends from the angled
manifold branch proximal end 23. A filter 72 aligns at the mouth of
the branch passage 50. The filter 72 and a Luer fitting (not
illustrated) can be used to prevent any particulate outflow, to
provide for metered outflow, or, alternatively, to provide suction
for fluid or particle evacuation.
Luer fitting 26 is utilized to secure the strain relief 30 and the
guide catheter 32 to the distal manifold end 28. The strain relief
30 is comprised of a tube 31, a central bore 74 internal to the
tube 31 which accommodates the guide catheter 32, an annular flange
76 about the tube 31, and a tapered proximal tube mouth end 78. It
is noted that the outer diameter of the tube 31 is constant from
the annular flange 76 to the distal tube end 80, and that the outer
diameter steadily decreases from the annular flange 76 to the
tapered proximal tube mouth end 78 to provide a tapered tube
surface 82 which conforms, for purpose of a proper fit, to the
taper of the tapered central passage surface 88 of the central
passage 48. The tapered proximal tube mouth end 78 allows for
easily accomplished alignment of guidewires and other assemblies,
such as inner assembly 14 and the like, with a lumen 87 located in
the guide catheter 32. The Luer fitting 26 includes threads 84
which threadingly engage corresponding threads 86 at the distal end
28 of the manifold 16. The Luer fitting 26 bears against the
annular flange 76 of the strain relief 30 to force the tapered tube
surface 82 of the strain relief 30 against the tapered central
passage surface 88 of the central passage 48 to effect a suitable
seal.
FIG. 4 illustrates a longitudinal sectional view of the filter
housing/high pressure connection assembly 36 located at the
hypo-tube proximal end 38 of the hypo-tube 34, where all numerals
correspond to those elements previously described. The filter
housing/high pressure connection assembly 36 includes a
cylindrical-like body 90 having a threaded surface 92, a tubular
cavity 94, fine and course filters 96 and 98 residing in the
tubular cavity 94, a central passage 100 extending through the body
90 and connecting to the tubular cavity 94, and a plug-like cap
102, having a central bore 104, extending into the tubular cavity
94 of the body 90. The hypo-tube 34 suitably secures within the
central bore 104 of the cap 102. The central passage 100
communicates through fine and course filters 96 and 98 with the
lumen 106 of the hypo-tube 34.
FIG. 5 illustrates a side view of the transitional stop 40, the jet
cap 44 and the guidewire coil 46 aligned over and about the
hypo-tube 34 near or at the hypo-tube distal end 42, where all
numerals correspond to those elements previously described. The
relative sizes of the transitional stop 40 and the jet cap 44 with
respect to each other and with respect to the sizes of the lumen 87
of the guide catheter 32 and a stationary stop 150 residing in the
guide catheter 32, as well as details of the transitional stop 40,
are discussed in detail below with relation to FIGS. 6, 12 and
13.
FIG. 6 illustrates an isometric view of the transitional stop 40,
where all numerals correspond to those elements previously
described. The one-piece transitional stop 40 includes a tubular
body 108 having a central bore 110 and a plurality of guide bars
112a-112n extending radially from the tubular body 108. Guide bars
112a-112n include angled leading edges 114a-114n extending from the
leading portion of the body 108 to arced surfaces 116a-116n. The
angled leading edges 114a-114n contact a stationary stop 150 in the
guide catheter 32, as later described in detail. Preferably, and
for purposes of example and illustration, the arced surfaces
116a-116n describe arcs centered on the longitudinal axis of the
tubular body 108; but, in the alternative, the arced surfaces
116a-116n could describe arcs having other centers, or the surfaces
could be flat or be of other geometric design, and shall not be
construed to be limiting to the scope of the invention.
FIG. 7 illustrates a longitudinal sectional view, taken along line
7--7 of FIG. 5, of the transitional stop 40, the jet cap 44 and the
guidewire coil 46 aligned and secured over and about the hypo-tube
34 near or at the hypo-tube distal end 42; and FIG. 8 illustrates a
view of the jet cap 44 looking in the direction of line 8--8 of
FIG. 7, where all numerals correspond to those elements previously
described. The central bore 110 of the transitional stop 40 is
aligned and appropriately secured over and about the last hypo-tube
portion 34n to affix the transitional stop 40 over and about and
near the hypo-tube distal end 42. The proximal end of the
transitional stop 40 juxtaposes and abuts the shoulder-like
transition 117 between the next to the last hypo-tube portion 34g
and the last hypo-tube portion 34n. The jet cap 44 aligns over and
about and is secured to the last hypo-tube portion 34n at the
hypo-tube distal end 42. As shown in FIGS. 7 and 8, the jet cap 44
is tubular and includes a circular peripheral wall 118 and a
circular end wall 120 extending inwardly from one end of the
circular peripheral wall 118. Central to the circular end wall 120
is an elongated hole 122 having arcuate ends and opposite sides
each having an arcuate mid section and straight portions extending
oppositely from the arcuate mid section to the opposite arcuate
ends, as shown in FIG. 8. The arcuate mid sections of the opposite
sides of the elongated hole 122 are positioned at the center of the
elongated hole 122 and are defined by opposing aligned arcuate
portions 124 and 126 of common radius. The last hypo-tube portion
34n aligns to and extends through the center of the elongated hole
122 and is embraced by the arcuate portions 124 and 126, thereby
dividing the elongated hole 122 into two jet orifices 128 and 130,
the jet orifice 128 being defined by the portion of elongated hole
122 to one side of the outer surface of the last hypo-tube portion
34n, and the jet orifice 130 being defined by the portion of
elongated hole 122 to the other side of the outer surface of the
last hypo-tube portion 34n. At the distal end of the circular
peripheral wall 118 is a weld 132 which joins together the circular
peripheral wall 118, the extreme tip of the distal end 42 of the
hypo-tube 34, the guidewire coil 46 and a tapered core 134. A
plurality of orifices including orifices 136 and 138 in the distal
end 42 of hypo-tube 34 align within the central cavity 140 of the
jet cap 44 for fluid communication from lumen 106 to the central
cavity 140 and to the two jet orifices 128 and 130. A weld 142 is
also included at the distal end of the guidewire coil 46 to secure
the end of the tapered core 134 to the guidewire coil 46 and to
provide for smooth entry into a vessel or other body cavity.
FIG. 9 illustrates a slightly modified version of the jet cap 44
wherein two distinct jet orifices 144 and 146 are included in the
circular end wall 120 in lieu of the elongated hole 122 shown in
FIG. 8, and wherein a bore 148 in the circular end wall 120
accommodates the last hypo-tube portion 34n.
FIG. 10 illustrates a longitudinal sectional view of the guide
catheter distal end 33 of the guide catheter 32 taken along line
10--10 of FIG. 2, where all numerals correspond to those elements
previously described. Illustrated in particular is the
multi-radiused stationary stop 150 frictionally engaging the lumen
87 at the guide catheter distal end 33. One outer radius defines
the cylindrical body 152, which frictionally engages lumen 87, and
another larger outer radius defines a cap 153 at the end of the
stationary stop 150. A central bore 154 aligns coaxially within the
cylindrical body 152 and the cap 153. An annular shoulder 156
between the cap 153 and the cylindrical body 152 abuts and aligns
to the guide catheter distal end 33. An angled annular surface 158,
which is complementary to the angled leading edges 114a-114n of the
transitional stop 40 shown in FIG. 6, is included at the proximal
end of the cylindrical body 152. An annular crimp sleeve 160
applied over and about the guide catheter distal end 33 ensures a
positive fixation of the stationary stop 150 in the lumen 87.
FIG. 11 illustrates a longitudinal sectional view of the guide
catheter distal end with the jet cap 44 transiting the central bore
154 of the stationary stop 150 and with the transitional stop 40
aligned within the lumen 87 of the guide catheter 32, where all
numerals correspond to those elements previously described.
FIG. 12 illustrates a longitudinal sectional view of the guide
catheter distal end with the transitional stop 40 aligned within
the lumen 87 of the guide catheter 32 and in mutual engagement with
the stationary stop 150, where all numerals correspond to those
elements previously described. Mutual engagement of the stationary
stop 150 with the transitional stop 40 positions the jet cap 44 at
a desirable and finite distance from the stationary stop 150 at the
guide catheter distal end 33.
Tubular guide catheter 32 may be constructed of a flexible polymer
material and is characterized by an ability to follow over a
flexible guidewire through the vasculature of a patient to be
treated. Since the tubular guide catheter 32 may also be subjected
to reduced or vacuum pressures in some applications, the tubular
guide catheter 32 should be resistant to collapse or bursting at
the pressure differentials employed. Again, for purposes of example
and illustration, the guide catheter 32 can have an outer diameter
of about 4 French or smaller, or an outer diameter of about 0.040
inch, and an inner diameter of about 0.028 inch which can also
taper in diameter. As is well known in the art, the guide catheter
32 may be advanced and maneuvered through the vasculature such that
the guide catheter distal end 33 may be selectively positioned
adjacent to the site of desired surgical action, for example,
adjacent to a thrombus obstructing a blood vessel.
The stationary stop 150 may be formed from a variety of materials.
Preferably, the stationary stop 150 is formed of material identical
to that of the guide catheter 32.
The transitional stop 40 is mounted in the hypo-tube 34 at a
location spaced apart from the hypo-tube distal end 42 and distal
from the hypo-tube portion 34g. The transitional stop 40 has a
cross sectional extent such that it may not freely pass the
stationary stop 150. The transitional stop 40 has a substantially
X-shaped cross section when viewed axially, as in FIG. 13, which
allows for fluid passage in a proximal direction. However, as will
be discussed subsequently, numerous alternative shapes might be
employed for the transitional stop 40 provided that at least
passage of the transitional stop past the stationary stop 150 is
prevented. Preferably, the distal portion of the transitional stop
40 includes tapered surfaces, such as angled leading edges
114a-114n. The jet cap 44 presents a cross section capable of
passing through the central bore 154 of the stationary stop 150.
The angled leading edges 114a-114n serve, in juxtaposition with the
angled annular surface 158 of the stationary stop 150, to desirably
longitudinally position the transitional stop 40 relative to the
stationary stop 150. The close longitudinal alignment of the
plurality of guide bars 112a-112n within the lumen 87 of the guide
catheter 32 generates lateral spaced relations, such as, for
example, a concentric relationship between the first tube or guide
catheter 32 and the second tube or hypo-tube 34, respectively.
Preferably, the cross sectional extent of the transitional stop 40
is roughly about 0.010 inch to about 0.030 inch; however, the
critical consideration in cross sectional dimensions of the
transitional stop 40 is that it must pass through the lumen 87 of
the first tube or guide catheter 32 and yet not pass the stationary
stop 150.
The jet cap 44 is mounted at the distal end 42 of the hypo-tube 34
and includes a guidewire coil 46 extending distally from the jet
cap 44. In a preferred embodiment, the jet cap 44, guidewire coil
46 and transitional stop 40 are radially symmetrical about the
longitudinal extent of the hypo-tube 34. In such an embodiment, the
jet cap 44 preferably has a diameter of from about 0.010 inch to
about 0.030 inch. The hypo-tube 34 preferably has an outer diameter
of about 0.008 inch to about 0.018 inch and also includes a
continuous high pressure lumen 106 extending from the hypo-tube
proximal end 38 to the hypo-tube distal end 42 and continuing into
the jet cap 44. When the hypo-tube distal end 42 of the hypo-tube
34 is advanced through the lumen 87 of the guide catheter 32, the
guidewire coil 46 and the jet cap 44 and any portion of the
hypo-tube 34 distal from the transitional stop 40 are free to pass
the location of the stationary stop 150. However, passage of the
transitional stop 40 is prevented by the partial obstruction of the
lumen 87 of guide catheter 32 by the stationary stop 150. Thus,
when the distal angled leading edges 114a-114n of the transitional
stop 40 engage the angled annular surface 158 of the stationary
stop 150, a desired longitudinal relationship is dependably
generated between the jet cap 44 and the guide catheter distal end
33 (at the cap 153) of the guide catheter 32. Most importantly, the
jet cap 44 is oriented and spaced apart and distally situated at a
desired relationship to the guide catheter distal end 33 of the
guide catheter 32.
The jet cap 44 is preferably rounded or tapered at the distal end
to facilitate advancement of the hypo-tube 34 and to avoid catching
or snagging on the interior of the guide catheter 32, on the
stationary stop 150, or on a vessel wall when advanced beyond the
guide catheter distal end 33.
Fluid communication between the lumen 87 and the central bore 154
of the stationary stop 150 is allowed longitudinally and in a
distal direction about the geometry of the transitional stop 40. As
partially shown in FIGS. 5 and 6 and as fully shown in FIG. 13,
longitudinally oriented passages 162a-116n are formed. For example,
passage 162a is formed between guide bars 112a and 112b and a
portion of the periphery of transitional stop body 108 extending
from the proximal region of the transitional stop 40 distally
toward and including the angled leading edges 114a-114b.
Longitudinally oriented passages 162b-162n are formed in a
corresponding fashion. Note particularly that a portion of the
lumen 87 remains open where the transitional stop 40 interacts with
the stationary stop 150 to allow passage of liquid and small
portions of suspended tissue proximally through the guide catheter
32.
FIG. 13 illustrates a cross sectional view of the guide catheter
distal end 33 taken along line 13--13 of FIG. 12, where all
numerals correspond to those elements previously described.
Illustrated in particular are the plurality of passages 162a-162n
about the transitional stop 40 which allow passage of liquid and
small portions of suspended tissue proximally through the lumen 87
of the guide catheter 32. Although the guide bars 112a-112n include
planar side surfaces, other configurations having a rounded
intersection or even having non-planar intersecting walls or other
variations of longitudinal passages can be utilized and shall not
be construed to be limiting to the scope of the invention.
Mode of Operation
FIG. 14 best illustrates the mode of operation of the rheolytic
thrombectomy catheter 10 with particular attention to the guide
catheter distal end 33 and jet cap 44 positioned in a blood vessel
164, artery or the like at the site of a thrombotic deposit and
lesion 166.
A guidewire is first advanced percutaneously through the
vasculature to the site of the thrombotic deposit and lesion 166.
For a distal coronary vessel or a vessel of the brain, typically
the guidewire has a diameter of 0.010-0.016 inch. This invention
can also be applied to larger vessels which require larger diameter
guidewires. Once a guidewire has been advanced along the vessel 164
and has reached the thrombotic deposit and lesion, guide catheter
32, the first tube, which serves as a flexible evacuation tube, can
be advanced over the guidewire through tortuous turns to reach the
thrombotic deposit and lesion. With the guide catheter distal end
33 of the guide catheter 32 positioned near the thrombotic deposit
and lesion 166, the guidewire can then be removed from the guide
catheter 32 and the patient's body. The jet cap 44 at the terminus
of the second tube or hypo-tube 34 is then advanced within the
lumen 87 of the guide catheter 32 until the transitional stop 40
contacts the stationary stop 150 of the guide catheter 32.
The arced surfaces 116a-116n at the extremities of the guide bars
112a-112n of the transitional stop 40 provide for guidance of the
transitional stop 40 along the lumen 87 and also center the jet cap
44 in the center of the guide catheter 32 during initial transition
and provide for centering of the jet cap 44 in the central bore 154
of the stationary stop 150 prior to engagement of the transitional
stop 40 with the stationary stop 150. Engagement of the angled
leading edges 114a-114n with the stationary stop 150 sets a
predetermined gap or distance from the jet cap 44 proximal end to
the stationary stop 150. The central bore 154 and lumen 87 of the
guide catheter 32 serve as an evacuation tube at the guide catheter
distal end 33. The rheolytic thrombectomy catheter 10 can then be
activated by providing high pressure liquid, preferably saline, to
the proximal end of the guide catheter 32 via the manifold 16.
High pressure saline, or other liquid, from the manifold 16 is
provided and flows through the lumen 106 of the hypo-tube 34 to
exit orifices 136 and 138 leading to the central cavity 140 of the
jet cap 44. The high pressure saline exits jet orifices 128 and 130
as retrograde jets 170 of high velocity saline being directed
toward the open central bore 154 in the stationary stop 150 at the
guide catheter distal end 33. The high velocity saline jets 170
dislodge tissue from the thrombotic deposit and lesion 166 and
entrain it into the saline jets 170 where it is broken up into
smaller fragments. Impingement of the saline jets 170 onto the
guide catheter distal end opening creates a stagnation pressure
within the evacuation lumen 87 that drives the debris particles of
tissue from the thrombotic deposit and lesion 166 toward the
proximal end of the guide catheter 32.
A positive displacement piston PUMP (not illustrated) can be used
to provide liquid, preferably saline, under pressure to the
proximal end of the hypo-tube 34. A pressure ranging from
500-15,000 psi will provide the energy to create a useful high
velocity jet as the saline exits the jet orifices 128 and 130
located at the circular end wall 120 of the jet cap 44. The flow
rate of saline can be controlled by adjusting the pumping rate of
the positive displacement pump. The proximal end of the guide
catheter 32 interfaces with a suction device through the Luer
connection 22 at the manifold branch 24, for example, a roller
pump, prior to discharge of the evacuated thrombotic debris into a
collection bag for disposal. The rate of evacuation can be
controlled by adjusting the rate of the roller pump. The rate of
saline inflow can be balanced with the rate of removal of
thrombotic debris by simultaneous adjustment of the piston pump and
the roller pump. The rate of saline inflow can be less than, equal
to, or greater than the rate of removal of thrombotic debris. The
rate of thrombus removal can be set to slightly exceed the rate of
saline inflow to reduce the likelihood for distal embolization of
thrombotic tissue.
Alternative Embodiments
FIG. 15, a first alternative embodiment, illustrates a longitudinal
sectional view of the transitional stop 40, an alternative jet cap
180, in lieu of jet cap 44, and a guidewire coil 46a aligned and
secured over and about the hypo-tube 34 near or at a hypo-tube
distal end 42a; and FIG. 16 illustrates a view of the jet cap 180
looking in the direction of line 16--16 of FIG. 15, where all
numerals correspond to those elements previously described. The jet
cap 180 includes several like components as described previously.
The jet cap 180 aligns over and about and is secured to the last
hypo-tube portion 34na, which angles downwardly from the
longitudinal axis of the hypo-tube 34 at the hypo-tube distal end
42a. The jet cap 180 is tubular and includes a circular peripheral
wall 118a and a circular end wall 120a extending inwardly from one
end of the circular peripheral wall 118a. Located in the circular
end wall 120a are two holes 182 and 184 which support a U-shaped
hypo-tube portion 34x extending from the last hypo-tube portion
34na. The U-shaped hypo-tube portion 34x aligns to and extends
through the holes 182 and 184 in the circular end wall 120a, as
well as through the jet cap central cavity 140a. The free end
portion of the U-shaped hypo-tube portion 34x secures in the hole
184 flush with the circular end wall 120a and is open, thereby
defining an orifice aligned to direct a high velocity jet stream,
preferably saline, in a proximal direction in a manner and fashion
such as previously described. At the distal end of the circular
peripheral wall 118a is a weld 132a which joins together the
circular peripheral wall 118a, the bight of the U-shaped portion
34x of the hypo-tube 34, the guidewire coil 46a and a tapered core
134a. A weld 142a is also included at the distal end of the
guidewire coil 46a to secure the end of the tapered core 134a to
the guidewire coil 46a and to provide for smooth entry into a
vessel or other body cavity.
FIG. 16 is a view of the proximal end of the first alternative jet
cap embodiment looking in the direction of line 16--16 of FIG. 15,
where all numerals correspond to those elements previously
described.
FIG. 17, a second alternative embodiment, illustrates a
longitudinal sectional view of the transitional stop 40, an
alternative jet cap 200, in lieu of jet cap 44, and a guidewire
coil 46b aligned and secured over and about the hypo-tube 34 near
or at a hypo-tube distal end 42b; and FIG. 18 illustrates a view of
the jet cap 200 looking in the direction of line 18--18 of FIG. 17,
where all numerals correspond to those elements previously
described. The jet cap 200 includes several like components as
described previously. The jet cap 200 aligns over and about and is
secured to the last hypo-tube portion 34nb, which angles downwardly
from the longitudinal axis of the hypo-tube 34 at the hypo-tube
distal end 42b. The jet cap 200 is tubular and includes a circular
peripheral wall 118b and a circular end wall 120b extending
inwardly from one end of the circular peripheral wall 118b. Located
in the circular end wall 120b is a hole 202, and, preferably, a
centrally located jet orifice 206. Preferably one jet orifice is
included, although more jet orifices can be utilized and shall not
be deemed as limiting to the scope of the invention. The last
hypo-tube portion 34nb aligns to and extends through the hole 202
in the circular end wall 120b and has an open end or orifice which
ends in the jet cap central cavity 140b of the jet cap 200 for
fluid communication from lumen 106 to the central cavity 140b and
to the jet orifice 206 to direct a high velocity jet stream,
preferably saline, in a proximal direction in a manner and fashion
such as previously described. At the distal end of the circular
peripheral wall 118b is a weld 132b which joins together the
circular peripheral wall 118b, the guidewire coil 46b and a tapered
core 134b. A weld 142b is also included at the distal end of the
guidewire coil 46b to secure the end of the tapered core 134b to
the guidewire coil 46b and to provide for smooth entry into a
vessel or other body cavity.
FIG. 18 is a view of the proximal end of the second alternative jet
cap embodiment looking in the direction of line 18--18 of FIG. 17,
where all numerals correspond to those elements previously
described.
FIG. 19, a third alternative embodiment, illustrates a longitudinal
sectional view of a transitional stop 210, a jet cap 212 being
similar to the configuration of jet cap 180 of FIG. 15 and in lieu
of jet cap 44, and a guidewire coil 46c, being similar in
configuration to guidewire coil 46a, aligned and secured over and
about the hypo-tube 34 near or at a non-angled hypo-tube distal end
42c; and FIG. 20 illustrates a view of the guide catheter distal
end 33 looking in the direction of line 20--20 of FIG. 19, where
all numerals correspond to those elements previously described. In
this embodiment the jet cap 212 aligns over and about and is
secured to the last hypo-tube portion 34nc which projects straight
outwardly from the lumen 87 and from transitional stop 210. The
longitudinal axis of the hypo-tube 34 and the last hypo-tube
portion 34nc is offset from the central axis of the transitional
stop 210, at the hypo-tube distal end 42c. Having the last
hypo-tube portion 34nc located off-center obviates the requirement
of having a last hypo-tube portion which angles downwardly from the
longitudinal axis of the hypo-tube 34 and also allows the jet cap
212 to align with the central bore 154 of the stationary stop 150
without having an angled last hypo-tube portion. The transitional
stop 210 is fashioned of a solid material having a circular cross
section, one end of which is in the form of a truncated cone having
an angled annular surface 214 and also having a longitudinally
oriented hole 216 distant from the central longitudinal axis of the
transitional stop 210 and, in addition, a longitudinally oriented
lumen 218 distant from the central longitudinal axis of the
transitional stop 210. The transitional stop 210 is positioned as
illustrated to position the angled annular surface 214 against the
angled annular surface 158 of the stationary stop 150 to position
the jet cap 212 at a desirable and finite distance from the
stationary stop 150 at the guide catheter distal end 33 so that a
high velocity jet stream, preferably saline, emanating from the
open end or orifice of the hypo-tube may be directed in a proximal
direction in a manner and fashion toward the lumen 218 to dislodge,
break up and carry away thrombotic tissue debris, such as
previously described.
FIG. 20 illustrates a view of the guide catheter distal end 33
looking in the direction of line 20--20 of FIG. 19, where all
numerals correspond to those elements previously described.
FIG. 21, a fourth alternative embodiment, illustrates a
longitudinal sectional view of a guide catheter distal end 33a and
having alternatively configured stationary and transitional stops,
where all numerals correspond to those elements previously
described. Located at the guide catheter distal end 33a of the
guide catheter 32 is a stationary stop 230. The stationary stop 230
is permanently connected to, molded to, or otherwise formed to the
tubing wall of the guide catheter 32 and projects into the lumen 87
of the guide catheter 32. By projecting inward and into the lumen
87, the stationary stop 230, being comprised of a plurality of
arcuate stops 230a-230n, partially obstructs the lumen 87. However,
the stationary stop 230 does not fully obstruct the lumen 87.
Moreover, the stationary stop 230 allows for free passage of a
standard guidewire through the lumen 87 in the region adjacent the
guide catheter distal end 33a of the guide catheter 32. Preferably,
and for purposes of example and illustration, the arrangement and
dimensions of the stationary stop 230 are such that a coronary or
neurological guidewire having a diameter of at least 0.010 inch,
more preferably 0.016 inch, can freely pass the stationary stop
230. Most preferably, the unobstructed diameter of the stationary
stop 230 is from about 0.010 inch to about 0.030 inch. The guide
catheter 32 has an outer diameter of about 0.040 inch and an inner
diameter of about 0.028 inch or about 4 French or smaller. As is
well known in the art, the guide catheter 32 may be advanced and
maneuvered through the vasculature such that the guide catheter
distal end 33a may be selectively positioned adjacent to the site
of desired surgical action, for example, adjacent to a thrombus
obstructing a blood vessel.
The stationary stop 230 has a plurality of arcuate stops 230a-230n
aligned parallel to the central axis of the guide catheter 32, each
having a proximal tapered surface 234a-234n and a distal tapered
surface 236a-236n. The stationary stop 230 may be formed from a
variety of materials. Preferably, the stationary stop 230 is formed
of material identical to that of the guide catheter 32. Most
preferably, the stationary stop 230 is fabricated by a permanent
deformation and thickening of the wall of the guide catheter 32 at
the desired location. Alternatively, the stationary stop 230 might
be separately constructed and then fixed within the guide catheter
32.
The hypo-tube 34, or second tube, is fashioned as previously
described having a hypo-tube distal end 42d and a proximal end (not
shown). A transitional stop 238 is mounted on the last hypo-tube
portion 34nd at a location spaced apart from a jet cap 240 and a
guidewire coil 46d also mounted on the last hypo-tube portion 34nd.
The transitional stop 238 has a cross sectional extent such that it
may not freely pass the stationary stop 230. In one embodiment, the
transitional stop 238 has a rounded cross section when viewed
axially. However, numerous alternative shapes might be employed for
the transitional stop 238 provided that at least passage past the
stationary stop 230 is prevented. Preferably, the distal surface
242 of the transitional stop 238 is tapered, such that a distalmost
extent of the transitional stop 238 presents a cross section
capable of passing the proximalmost extent of the stationary stop
230, generally as represented by the proximal tapered surfaces
234a-234n. Distal tapered surface 242 serves a dual function by
first facilitating passage and advancement of the hypo-tube 34 by
reducing any tendency to catch or bind within the guide catheter
32, and second, to desirably laterally position the transitional
stop 238 relative to the stationary stop 230 and thereby generate
lateral relations, such as for example, a concentric relationship
between the guide catheter 32 and hypo-tube 34, respectively.
Preferably, the cross sectional extent of the transitional stop 238
is roughly about 0.010 inch to about 0.030 inch; however, the
critical consideration in cross sectional dimensions of the
transitional stop 238 is that it must pass through the lumen 87 of
the guide catheter 32 and yet not pass the stationary stop 230.
As previously mentioned, a jet cap 240 is mounted at the hypo-tube
distal end 42d of the hypo-tube 34. A guidewire coil 46d extends
distally from the jet cap 240. The jet cap 240, guidewire coil 46
and transitional stop 238 are radially symmetrical about the
longitudinal extent of the hypo-tube 34. The jet cap 240 preferably
has a diameter of from about 0.010 inch to about 0.030 inch. The
hypo-tube 34 preferably has an outer diameter of about 0.008 inch
to about 0.018 inch and also includes a continuous high pressure
lumen 106 extending from the proximal end to the hypo-tube distal
end 42d and continuing into the jet cap 240. When the end of the
hypo-tube 34 is advanced through the lumen 87 of the guide catheter
32, the guidewire coil 46d adjacent the jet cap 240 and any portion
of the hypo-tube 34 distal from the transitional stop 238 are free
to pass the location of the stationary stop 230. However, passage
of the transitional stop 238 is prevented by the partial
obstruction of the lumen 87 of guide catheter 32 by the stationary
stop 230. Thus, when the distal tapered surface 242 of the
transitional stop 238 engages the proximal tapered surfaces
234a-234n of the stationary stop 230, a desired longitudinal
relationship is dependably generated between the jet cap 240 and
the guide catheter distal end 33a. Most importantly, the jet cap
240 is oriented and spaced apart and distally situated at a desired
relationship to the distal end 33a of the guide catheter 32.
FIG. 22 illustrates a view of the guide catheter distal end 33a
looking in the direction of line 22--22 of FIG. 21, where all
numerals correspond to those elements previously described.
Illustrated in particular are the plurality of arcuate stops
230a-230n shown in contact with the distal tapered surface 242 of
the transitional stop 238. Fluids containing thrombotic debris can
pass between the arcuate stops 230a-230n, along the inner wall of
the guide catheter 32 which is adjacent to and between the arcuate
stops 230a-230n, along the transitional stop 238, and into the
lumen 87 of the guide catheter 32 for passage to the manifold
16.
FIG. 23, a fifth alternative embodiment, illustrates, in partial
cross section, a side view of the guide catheter distal end 33
where the hypo-tube 34 is fixed along the longitudinal axis of the
guide catheter 32, where all numerals correspond to those elements
previously described. In this embodiment of a one-piece catheter,
the hypo-tube 34 is appropriately aligned and secured in a central
bore 244 of a cylindrical fixture 246 which secures in the end of
the guide catheter 32 by a crimp sleeve 248. A jet cap 250 and a
guidewire coil 46e secure to the hypo-tube distal end 42e at the
last hypo-tube portion 34ne at a fixed distance from the guide
catheter distal end 33. In this embodiment, no transitional or
stationary stops are incorporated, as the entire catheter system
incorporating a longitudinally fixed hypo-tube 34 is inserted into
the body without use of a guidewire. The cylindrical fixture 246
has passages with the same profile as passages 162a-162n of the
transitional stop 40 for connection to lumen 87 in the guide
catheter 32.
Because numerous modifications may be made to this invention
without departing from the spirit thereof, the scope of the
invention is not to be limited to the embodiments illustrated and
described. Rather, the scope of the invention is to be determined
by the appended claims and their equivalents. The tip can be
radio-opaque. The guidewire can be a braided polymer or other
suitable material.
While each of the the parts 44, 180, 200, 212, 240, and 250
representing means positioned at the distal end of the high
pressure tube and coacting with the distal end of the high pressure
tube for directing fluid toward the open end of the evacuation tube
has been characterized throughout the description as a "jet cap",
it is here pointed out that this term "jet cap" is not of common
usage in the art but, rather, has been introduced as a convenient
expression by which to indicate the general character of these
parts, in that they act in the nature of a cap at the distal end of
the high pressure tube and serve in coaction with the distal end of
the high pressure tube to direct one or more jets of fluid
proximally toward the open distal end of the evacuation tube.
Accordingly, the term "jet cap" is not to be construed in a
limiting sense as defining a particular structure, but is to be
regarded as merely signifying the general nature of the
instrumentally provided for directing fluid in the manner
described.
While each of the parts 44, 180, 200, 212, 240 and 250 representing
means positioned at the distal end of the high pressure tube and
coacting with the distal end of the high pressure tube for
directing fluid toward the open end of the evacuation tube has been
characterized thoughout the description as a "jet cap", it is here
pointed out that this term "jet cap" is not of common usage in the
art but, rather, has been introduced as a convenient expression by
which to indicate the general character of these parts, in that
they act in the nature of a cap at the distal end of the high
pressure tube and serve in coaction with the distal end of the high
pressure tube to direct one or more jets of fluid proximally toward
the open distal end of the evacuation tube. Accordingly, the term
"jet cap" is not to be construed in a limiting sense as defining a
particular structure, but is to be regarded as merely signifying
the general nature of the instrumentally provided for directing
fluid in the manner described.
* * * * *